She said she had been beaten by Mateen during outbursts of temper in which he would "express hatred towards everything."

Eventually, she was "rescued" from Mateen by members of her family who intervened four months into a stormy marriage that ultimately ended in divorce, she said.

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"I know he had a history of steroids," Yusufiy told reporters outside a home where she was staying with a man she identified as her current fiancee. She also described Mateen as "emotionally unstable," "mentally ill" and bipolar.

"In the beginning he was a normal being that cared about family, loved to joke, loved to have fun,” Mrs Yusufiy said, adding that she had met Mateen online.

"A few months after we were married I saw his instability, I saw his bipolar, and he would get mad out of nowhere, and that’s when I started worrying about my safety.

“Then after a few months he started abusing me physically, very often, and not allowing me to speak to my family, and keeping me hostage from them."

Gunman Omar Mateen

She said that Mateen, who had a gun licence, owned a silver pistol. She also revealed that at one point Mateen harboured ambitions to become a police officers.

Though she said he did not show any outward displays of extremism, an Imam at Mateen's local mosque said he was known for being "aggressive."

And former Fort Pierce police officer Daniel Gilroy described Mateen as mentally "unhinged," having gotten to know the shooter when they worked late shifts together at G4S.

He also said Mateen frequently made comments that were homophobic and racist during his shifts.